<template>
  <div>
    <!-- 面包屑导航区 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>分类参数</el-breadcrumb-item>
    </el-breadcrumb>

    <!-- 卡片视图区域 -->
    <el-card>
      <!-- 警告区域 -->
      <el-alert
        title="注意：只允许为第三级分类设置相关参数！"
        type="warning" :closable="false" show-icon>
      </el-alert>

      <!-- 选择商品分类区域 -->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类：</span>
          <!-- 选择商品分类的级联选择框 -->
          <el-cascader
            v-model="selectedKeys"
            :options="cateList"
            :props="{ expandTrigger: 'hover', value: 'cat_id', label: 'cat_name', children: 'children' }"
            @change="handleChange"></el-cascader>
        </el-col>
      </el-row>

      <!-- tab页签区域 -->
       <el-tabs v-model="activeName" @tab-click="handleClick">
         <!-- 添加动态属性的面板 -->
        <el-tab-pane label="动态参数" name="many">
          <!-- 添加动态属性的按钮 -->
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible = true">添加参数</el-button>
          <!-- 动态参数表格 -->
          <el-table :data="manyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <el-tag v-for="(item, i) in scope.row.attr_vals" :key="i" closable @close="handleClose(scope.row, i)">{{item}}</el-tag>
                <!-- 输入的文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">修改</el-button>
                <el-button type="danger" icon="el-icon-edit" size="mini" @click="deleteParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态属性的面板 -->
        <el-tab-pane label="静态属性" name="only">
          <!-- 添加静态属性的按钮 -->
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible = true">添加属性</el-button>
          <!-- 静态属性表格 -->
          <el-table :data="onlyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染tag标签 -->
                <el-tag v-for="(item, i) in scope.row.attr_vals" :key="i">{{item}}</el-tag>
                <!-- 输入的文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">修改</el-button>
                <el-button type="danger" icon="el-icon-edit" size="mini" @click="deleteParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>

    <!-- 添加参数的对话框 -->
    <el-dialog
      :title="'添加' + titleText"
      :visible.sync="addDialogVisible"
      width="50%" @closed="addDialogClosed">
      <!-- 添加参数的表单 -->
      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>

    <!-- 修改参数的对话框 -->
    <el-dialog
      :title="'修改' + titleText"
      :visible.sync="editDialogVisible"
      width="50%" @closed="editDialogClosed">
      <!-- 添加参数的表单 -->
      <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
 data () {
   return {
     //商品分类列表
     cateList: [],
     // 级联选择框双向绑定到的数组
     selectedKeys: [],
     activeName: 'many',
     // 动态参数的数据
     manyTableData: [],
     // 静态属性的数据
     onlyTableData: [],
     // 控制添加参数对话框的显示隐藏
     addDialogVisible: false,
     // 添加参数
     addForm: {
       attr_name: ''
     },
     // 添加参数的验证规则
     addFormRules: {
       attr_name: [
         { required: true, message: '请输入参数名称', trigger: 'blur' }
       ]
     },
     // 修改参数对话框的显示与隐藏
     editDialogVisible: false,
     // 修改参数的验证规则
     editFormRules: {
       attr_name: [
         { required: true, message: '请输入参数名称', trigger: 'blur' }
       ]
     },
     // 修改参数表单数据
     editForm: {
       attr_name: '',
       attr_id: ''
     },
     // 控制按钮与文本框的切换显示
     inputVisible: false,
     // 文本框的内容
     inputValue: ''

   }
 },
 created () {
   this.getCateList()
 },
 methods: {
   // 获取所有的商品分类列表
   async getCateList() {
     const {data: res} = await this.$http.get('categories')
     if (res.meta.status !== 200) {
       return this.$message.error('获取分类数据列表失败')
     }

     this.cateList = res.data
   },
   // 级联选择框选中项的变化，会触发这个函数
   handleChange() {
     this.getParamsData()
   },

   // tab页签点击事件的处理函数
   handleClick() {
     this.getParamsData()
   },

   // 获取参数数据
   async getParamsData() {
     // 证明选中的不是三级分类
     if (this.selectedKeys.length !== 3) {
       this.selectedKeys = []
       return 
     }

     const {data: res} = await this.$http.get(`categories/${this.cateId}/attributes`, {params: {sel: this.activeName}})
     if (res.meta.status !== 200) {
       return this.$message.error('获取参数列表失败')
     }

     res.data.forEach(item => {
       item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
       item.inputVisible = false
       item.inputValue = ''
     })
     
     if (this.activeName === 'many') {
       this.manyTableData = res.data
     } else {
       this.onlyTableData = res.data
     }
   },

   // 监听对话框关闭事件
   addDialogClosed() {
     this.$refs.addFormRef.resetFields()
   },

   // 点击按钮，添加参数
   addParams() {
     this.$refs.addFormRef.validate(async valid => {
       if(!valid) return

       const {data: ref} = await this.$http.post(`categories/${this.cateId}/attributes`, {
         attr_name: this.addForm.attr_name,
         attr_sel: this.activeName
       })
       if (ref.meta.status !== 201) {
         return this.$message.error('添加参数失败')
       }

       this.$message.success('添加参数成功')
       this.addDialogVisible = false
       this.getParamsData()
     })
   },

   // 点击按钮显示添加对话框
   async showEditDialog(attr_id) {
     const {data: res} = await this.$http.get(`categories/${this.cateId}/attributes/${attr_id}`)
     if (res.meta.status !== 200) {
       return this.$message.error('获取参数数据失败')
     }
     this.editForm = res.data

     this.editDialogVisible = true
   },

   // 监听修改参数对话框关闭
   editDialogClosed() {
     this.$refs.editFormRef.resetFields()
   },

   // 点击按钮修改参数信息
   editParams() {
     this.$refs.editFormRef.validate(async valid => {
       if (!valid) return

       const {data: res} = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`, {
         attr_name: this.editForm.attr_name,
         attr_sel: this.activeName
       })
      if (res.meta.status !== 200) {
        return this.$message.error('修改参数失败')
      }

      this.getParamsData()
      this.$message.success('修改参数成功')
      this.editDialogVisible = false
     })
   },

   // 删除参数
   deleteParams(attr_id) {
     this.$confirm('此操作将永久删除该文件, 是否继续?', '提示', {
          confirmButtonText: '确定',
          cancelButtonText: '取消',
          type: 'warning'
        }).then(async () => {
          const {data: res} = await this.$http.delete(`categories/${this.cateId}/attributes/${attr_id}`)
          if (res.meta.status !== 200) {
            this.$message.error('修改参数失败')
          }

          this.getParamsData()
          this.$message.success('修改参数成功')
        }).catch(() => {
          this.$message({
            type: 'info',
            message: '已取消删除'
          });          
        })
   },

   // 文本框失去焦点，或摁下了enter 都会触发
   async handleInputConfirm(item) {
     if (item.inputValue.trim().length === 0) {
       item.inputValue = ''
       item.inputVisible = false
       return 
     }

     item.attr_vals.push(item.inputValue.trim())
     this.saveAttrVals(item)
   },

   // 对attr_val的操作，提交到数据库
   async saveAttrVals(item) {
     const {data: res} = await this.$http.put(`categories/${this.cateId}/attributes/${item.attr_id}`, {
       attr_name: item.attr_name,
       attr_sel: this.activeName,
       attr_vals: item.attr_vals.join(' ')
     })
     if (res.meta.status !== 200) {
       return this.$message.error('编辑提交参数失败')
     }

     this.$message.success('编辑参数成功')
     item.inputValue = ''
     item.inputVisible = false
   },

   // 点击tag删除按钮删除参数
   handleClose(item, i) {
     item.attr_vals.splice(i, 1)
     this.saveAttrVals(item)
   },
   
   // 显示文本框
   showInput(item) {
     item.inputVisible = true
     // $nextTick是指在页面上的元素被重新渲染之后，才会调用回调函数中的代码
     this.$nextTick(_ => {
       this.$refs.saveTagInput.$refs.input.focus()
     })
   }
 },
 computed: {
   // 如果按钮需要被禁用，则返回true，否则返回false
   isBtnDisabled() {
     return this.selectedKeys.length !== 3
   },
   // 当前选中的三级分类的id
   cateId() {
     if (this.selectedKeys.length === 3) {
       return this.selectedKeys[2]
     }
     return null
   },
   // 动态计算标题的文本
   titleText() {
     return this.activeName === 'many' ? '动态参数' : '静态属性'
   }
 }
}
</script>

<style lang="less" scoped>
.cat_opt {
  margin: 15px 0;
}

.el-tag {
  margin: 10px;
}

.input-new-tag {
    width: 90px;
    margin-left: 10px;
  }

.button-new-tag {
  margin-left: 10px;
}
</style>